Human movement patterns can become disordered as a result of injury, or other causes. In general, someone whose movement has problems goes to a physical therapist. The physical therapist would attempt to explain the problem, and how to move properly to the patient. However, this can be difficult to do, and the subject may have difficulty understanding how their movement and balance should be altered. When learning to play a sport or dance, a coach generally attempts to explain how to move properly. In these cases as well, the subject may have difficulty understanding how their movement should be altered.